cleaning marble sinks.
Hi Diana here is some information that will help you clean your marble sink.
Marble I’d porous so take a sponge and put bleach on it let it sit on the spot over night
Marble needs safe cleaners and sealer. Don't use anything abrasive or acidic. If the marble cleaner doesn't work, contact a local installer for cleaning advice. They may be able to recommend the product you need.
This article does not recommend bleach. I'd use hydrogen peroxide instead. There are several methods in this article. Take a look to see which one you'd like. :) Wishing you the best.